I’ve been doing it wrong all along!

I hear that statement quite often, especially when I mention that soiled pizza boxes (and paper towels, and paper bread wrappers, and…) are NOT recyclable and do not go into your blue curbside recycling cart.

And the conversation usually continues with a: But wait, why aren’t they recyclable? – they are made out of paper.

Well, inquisitive mind, I am glad you asked. Soiled paper products in blue recycling carts are what we in industry terms call contaminants. Paper recycling facilities break down paper using water and creating what is known as a “slurry” – separating the paper into fibers. When those fibers are covered in grease and food… well, just think of that age old saying: water and oil don’t mix (flashback to my first boyfriend). That oil rises to the top of the slurry and it’s impossible to separate the paper fibers from the oil, thus ruining entire batches of paper fiber for recycling.

So where do your greasy boxes that delivered joyous deliciousness to you go? Your brown curbside compost cart (note: this is true for City of Napa and Unincorporated Napa County residents – Upper Valley and City of American Canyon service providers do not permit paper-based products in compost carts at this time).

My favorite saying that I use in all my outreach and trainings is: anything that was ever alive, plant or animal, can go into your brown compost cart. And yes, that cardboard box is made out of a tree ;). Glass, plastics and metals … none of these base material types are compostable (fun fact: while not compostable, glass and metals are continuously recyclable meaning that they never wear out … they just get dirty!)

Common compostable materials include: pizza boxes, paper towels, fast food paper to go bags, butcher paper, wax paper, paper plates, paper to go boxes, meats, bones, dairy, vegetables, fruits, shells, chicken poop, untreated wood, tea bags, coffee grounds, and so many more items (yes, even those items with a wax or poly coating). Check out www.NapaRecycling.com for a full list of all items accepted in your brown compost cart.

Please note: dog and cat poop do not belong in your brown compost cart – rather it needs to go into your landfill/trash cart. Why? The feces of domesticated meat-eating animals, specifically dogs and cats, can carry a number of unhealthy parasites and bacteria that need high temperatures for a long period of time to be killed, which we cannot guarantee at our facility. Feces from non-meat eating animals like horses, chickens, sheep, rabbits and birds can go into your brown compost cart (including the sawdust from animal bedding).

Additionally (because I participate in waste characterizations and hand sort recyclables for hours on end): diapers are not recyclable nor compostable – they too belong in the landfill/trash container (and yes, I’ve sorted diapers before from a recycling load…)

I recently enjoyed a conversation with a Napa resident who told me his favorite saying: if it goes in the brown, it goes back into the ground – and he is right (I received permission to use his saying)! When you put your food scraps, soiled paper, and yard trimmings into your brown cart, it is turned into compost that is used by local vineyards, landscapers, home owners, and so many more throughout our community to amend their soils.

I also recently heard a new saying that has upgraded my when in doubt, throw it out (aka landfill it) – I am now recommending:

When in doubt, Find out!

A quick internet search does wonders.

Happy Composting … and keeping your recycling clean!

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This monthly column is written by Kendra Bruno, aka Compost Girl, who is the waste prevention specialist for the city of Napa. To submit questions, email kbruno@cityofnapa.org.